The present invention relates to compositions of poly(nucleic acid) polymers such as RNA or DNA polymers and polycations that are associated, either covalently or noncovalently, with block copolymers of alkylethers. The complexes are well suited for use as vehicles for delivering nucleic acid into cells.
The use of antisense poly(nucleic acids) to treat genetic diseases, cell mutations (including cancer causing or enhancing mutations) and viral infections has gained widespread attention. This treatment tool is believed to operate, in one aspect, by binding to xe2x80x9csensexe2x80x9d strands of mRNA encoding a protein believed to be involved in causing the disease state sought to be treated, thereby stopping or inhibiting the translation of the mRNA into the unwanted protein. In another aspect, genomic DNA is targeted for binding by the antisense polynucleotide (forming a triple helix), for instance, to inhibit transcription. See Helene, Anti-Cancer Drug Design, 6:569 (1991). Once the sequence of the mRNA sought to be bound is known, an antisense molecule can be designed that binds the sense strand by the Watson-Crick base-pairing rules, forming a duplex structure analogous to the DNA double helix. Gene Regulation: Biology of Antisense RNA and DNA, Erikson and Ixzant, eds., Raven Press, New York, 1991; Helene, Anti-Cancer Drug Design, 6:569 (1991); Crooke, Anti-Cancer Drug Design, 6:609 (1991). A serious barrier to fully exploiting this technology is the problem of efficiently introducing into cells a sufficient number of antisense molecules to effectively interfere with the translation of the targeted mRNA or the function of DNA.
One method that has been employed to overcome this problem is to covalently modify the 5xe2x80x2 or the 3xe2x80x2 end of the antisense polynucleic acid molecule with hydrophobic substituents. These modified nucleic acids generally gain access to the cells interior with greater efficiency. See, for example, Kabanov et al., FEBS Lett., 259:327 (1990); Boutorin et al., FEBS Lett., 23:1382-1390, 1989; Shea et al, Nucleic Acids Res., 18:3777-3783 (1990). Additionally, the phosphate backbone of the antisense molecules has been modified to remove the negative charge (see for example, Agris et al., Biochemistry, 25:6268 (1986); Cazenave and Helene in Antisense Nucleic Acids and Proteins. Fundamentals and Applications, Mol and Van der Krol, eds., p. 47 et seq., Marcel Dekker, New York, (1991) or the purine or pyrimidine bases have been modified (see, for example, Antisense Nucleic Acids and Proteins: Fundamentals and Applications, Mol and Van der Krol, eds., p. 47 et seq., Marcel Dekker, New York (1991); Milligan et al. in Gene Therapy For Neoplastic Diseases, Huber and Laso, eds., p. 228 et seq., New York Academy of Sciences, New York (1994). Other attempts to overcome the cell penetration barrier include incorporating the antisense poly(nucleic acid) sequence into an expression vector that can be inserted into the cell in low copy number, but which, when in the cell, can direct, the cellular machinery to synthesize more substantial amounts of antisense polynucleic molecules. See, for example, Farhood et al., Ann. N.Y. Acad Sci., 716:23 (1994). This strategy includes the use of recombinant viruses that have an expression site into which the antisense sequence has been incorporated. See, e.g., Boris-Lawrie and Temin, Ann. N.Y. Acad. Sci., 716:59 (1994). Others have tried to increase membrane permeability by neutralizing the negative charges on antisense molecules or other nucleic acid molecules with polycations. See, e.g. Kabanov et al., Soviet Scientific Reviews, Vol. 11, Part 2 (1992); 30 Kabanov et al., Bioconjugate Chemistry 4:448 (1993); Wu and Wu, Biochemistry, 27:887-892 (1988); Behr et al., Proc. Natl. Acad Sci U.S.A. 86:6982-6986 (1989). There have been problems with systemically administering poylnucleotides due to rapid clearance degradation and low bioavailability. In some cases it would be desirable to target polynucleotide molecules to a specific site in the body to specific target cells. Also, due to poor or low transport across biological barriers (such as the blood-brain to barrier) the transport of polynucleotides to targets across this barrier is decreased or impossible. Additionally, the problems with low oral or rectal bioavailability dramatically hinders the administration of such polynucleotides (including oligonucleotides).
Of course, antisense polynucleic acid molecules are not the only type of polynucleic acid molecules that can usefully be made more permeable to cellular membranes. To make recombinant protein expression systems, the expression-directing nucleic acid must be transported across the membrane and into the eukaryotic or prokaryotic cell that will produce the desired protein. For gene therapy, medical workers try to incorporate, into one or more cell types of an organism, a DNA vector capable of directing the synthesis of a protein missing from the cell or useful to the cell or organism when expressed in greater amounts. The methods for introducing DNA to cause a cell to produce a new protein, ribozyme or a greater amount of a protein or ribozyme are called xe2x80x9ctransfectionxe2x80x9d methods. See, generally, Neoplastic Diseases, Huber and Lazo, eds., New York Academy of Science, New York (1994); Feigner, Adv. Drug Deliv. Rev., 5:163 (1990); McLachlin, et al., Progr. Nucl. Acids Res. Mol. Biol., 38:91 (1990); Karlsson, S. Blood, 78:2481 (1991); Einerhand and Valerio, Curr. Top. Microbiol. Immunol, 177:217-235 (1992); Makdisi et al., Prog. Liver Dis., 10:1 (1992); Litzinger and Huang, Biochim. Biophys. Acta, 11, 13:201 (1992); Morsy et al., JA.M.A., 270:2338 (1993); Dorudi et al., British J. Surgery, 80:566 (1993).
A number of the above-discussed methods of enhancing cell penetration by antisense nucleic acid are generally applicable methods of incorporating a variety of poly(nucleic acids) into cells. Other general methods include calcium phosphate precipitation of nucleic acid and incubation with the target cells (Graham and Van der Eb, Virology, 52:456, 1983), co-incubation of nucleic acid, DEAE-dextran and cells (Sompayrac and Danna, Proc. Natl. Acad. Sci., 12:7575, 1981), electroporation of cells in the presence of nucleic acid (Pofter et al., Proc. Natl. Acad. Sci., 81:7161-7165, 1984), incorporating nucleic acid into virus coats to create transfection vehicles (Gitman et al., Proc. Natl. Acad. Sci. U.S.A., 82:7309-7313, 1985) and incubating cells with nucleic acid incorporated into liposomes (Wang and Huang, Proc. Natl. Acad. Sci., 84:7851-7855, 1987).
Another problem in delivering nucleic acid to a cell is the extreme sensitivity of nucleic acids, particularly ribonucleic acids, to nuclease activity. This problem has been particularly germane to efforts to use ribonucleic acids as anti-sense oligonucleotides. Accordingly, methods of protecting nucleic acid from nuclease activity are desirable.
The invention relates to compositions of poly(nucleic acid) polymers such as RNA or DNA polymers and polycations that are associated, either covalently or noncovalently, with block copolymers of alkylethers. In a preferred embodiment, the poly(nucleic acids) are complexed with a polycation. The nucleic acid is stabilized by the complex and, in the complex, has increased permeability across cell membranes. Accordingly, the complexes are well suited for use as vehicles for delivering nucleic acid into cells.
The invention thus relates to compositions of poly(nucleic acid) polymers such as RNA or DNA polymers, and polycations that are associated (either covalently or noncovalently) with cationic block copolymers.
Structure of Block Copolymers
Block copolymers are most simply defined as conjugates of at least two different polymer segments (Tirrel, M. In: Interactions of Surfactants with Polymers and Proteins. Goddard E. D. and Ananthapadmanabhan, K. P. (eds.), CRC Press, Boca Raton, Ann Arbor, London, Tokyo, pp. 59-122, 1992). Some block copolymer architectures are presented below. 
The simplest block copolymer architecture contains two segments joined at their termini to give an A-B type diblock. Consequent conjugation of more than two segments by their termini yields A-B-A type triblock, A-B-A-B- type multiblock, or even multisegment A-B-C- architectures. If a main chain in the block copolymer can be defined in which one or several repeating units are linked to different polymer segments, then the copolymer has a graft architecture of, e.g., an A(B)n type. More complex architectures include for example (AB)n or AnBm starblocks which have more than two polymer segments linked to a single center.
In accordance with the present invention, all of these architectures can be useful for polynucleotide delivery, provided that they contain (a) at least one polycationic segment that will bind a polynucleotide (xe2x80x9cbinding segmentxe2x80x9d) and (b) at least one water soluble segment that will solubilize the complex formed between the block copolymer and polynucleotide (xe2x80x9csolubilizing segmentxe2x80x9d).
In accordance with the present invention, binding and solubilizing segments can be, independently of each other, linear polymers, randomly branched polymers, block copolymers, graft copolymers, star polymer, star block copolymer, dendrimers or have other architecture including but not limited to combinations of the above listed structures. For the purposes of the current invention all these structures are collectively called herein xe2x80x9cblock copolymersxe2x80x9d.
The degree of polymerization of the binding and solubilizing segments is between about 3 and about 10,000. More preferably, the degree of polymerization is between about 5 and about 2,000, still more preferably, between about 20 and about 1,000. The molecular weights of the binding and solubilizing segments is between about 600 and about 500,000. More preferably, the molecular weights are between about 1000 and about 100,000, still more preferably, between about 2000 and about 50,000.
Formulas XVIII-XXIII of the instant invention are diblocks and triblocks. At the same time, conjugation of polycation segments to the ends of polyether of formula XVII yields starblocks (e.g., (ABC)4 type). In addition, the polyspermine of examples 13-15 (below) are branched. Modification of such a polycation with poly(ethylene oxide) yields a mixture of grafted block copolymers and starblocks.
In one embodiment, the poly(nucleic acids) are complexed with a polycation. The nucleic acid is stabilized by the complex and, in the complex, has increased permeability across cell membranes. Accordingly, the complexes are well suited for use as vehicles for delivering nucleic acid into cells.
In a preferred first embodiment, the block copolymer is selected from the group consisting of polymers of formulas: 
wherein A and Axe2x80x2 are A-type linear polymeric segments, B and Bxe2x80x2 are B-type linear polymeric segments, and R1, R2, R3 and R4 are either block copolymers of formulas (I), (III) or (III) or hydrogen and L is a linking group, with the proviso that no more than two of R1, R2, R3 or R4 are hydrogen. In another preferred first embodiment of the invention, the polynucleotide composition further comprises a polycationic polymer comprising a plurality of cationic repeating units.
The composition provides an efficient vehicle for introducing polynucleotide into a cell. Accordingly, the invention also relates to a method of inserting poly(nucleic acid) into cells utilizing the first embodiment polynucleotide composition of the invention.
In a second embodiment, the invention provides a polynucleotide composition comprising:
(a) a polynucleotide or derivative thereof,
(b) a block copolymer having a polyether segment and a polycation segment, wherein the polyether segment comprises at least an A-type segment, and the polycation segment comprises a plurality of cationic repeating units.
In a preferred second embodiment, the copolymer comprises a polymer of formulas: 
wherein A, Axe2x80x2 and B are as described above, wherein R and Rxe2x80x2 are polymeric segments comprising a plurality of cationic repeating units, and wherein each cationic repeating unit in a segment may be the same or different from another unit in the segment. The polymers of this embodiment can be termed xe2x80x9cpolyether/polycationxe2x80x9d polymers. The R and Rxe2x80x2, segments can be termed xe2x80x9cR-typexe2x80x9d polymeric segments or blocks.
The polynucleotide composition of the second embodiment provides an efficient vehicle for introducing the polynucleotide into a cell.
Accordingly, the invention also relates to a method of inserting poly(nucleic acid) into cells utilizing the second embodiment composition of the invention.
In a third embodiment, the invention provides a polynucleotide composition comprising a polynucleotide derivative comprising a polynucleotide segment and a polyether segment attached to one or both of the polynucleotide 5xe2x80x2 and 3xe2x80x2 ends, wherein the polyether comprises an A-type polyether segment.
In a preferred third embodiment, the derivative comprises a block copolymer of formulas: 
wherein pN represents a polynucleotide having 5xe2x80x2 to 3xe2x80x2 orientation, and A, Axe2x80x2 and B are polyether segments as described above. In another preferred third embodiment, the polynucleotide complex comprises a polycationic polymer.
Polymers of formulas (I), (II), (III) or (IV) can also be mixed with each other or can be mixed either additionally or alternatively with one or more of the polymers of formula (V-a or b), (VI-a or b), (VII-a or b) and (VIII-a or b) and/or with polynucleotide derivatives of formulas (IX-a, b, c, or d), (X-a, b, c, d, e, or f, (XI), (XII) or (XIII) to provide an efficient vehicle for delivering poly(nucleic acid) to the interior of cells.
The polynucleotide composition of the third embodiment provides an efficient vehicle for introducing the polynucleotide into a cell. Accordingly, the invention also relates to a method of inserting poly(nucleic acid) into cells utilizing the third embodiment composition of the invention.
A fourth embodiment of the invention relates to a polyetherpolycation copolymer comprising a polymer, a polyether segment and a polycationic segment comprising a plurality of cationic repeating units of formula xe2x80x94NHxe2x80x94R0, wherein R0 is a straight chain aliphatic group of 2 to 6 carbon atoms, which may be substituted, wherein said polyether segments comprise at least one of an A-type of B-type segment. In a preferred fourth embodiment, the polycation polymer comprises a polymer according to formulas: 
wherein A, Axe2x80x2 and B are as described above, wherein R and Rxe2x80x2 are polymeric segments comprising a plurality of cationic repeating units of formula xe2x80x94NHxe2x80x94R0xe2x80x94, wherein R0 is a straight chain aliphatic group having from 2 to 6 carbon atoms, which may be substituted. Each xe2x80x94NHxe2x80x94R0xe2x80x94 repeating unit in an R-type segment can be the same or different from another xe2x80x94NHxe2x80x94R0xe2x80x94 repeating unit in the segment. A preferred fourth embodiment further comprises a polynucleotide or derivative.
In a fifth embodiment, the invention provides a polycationic polymer comprising a plurality of repeating units of formula: 
wherein R8 is:
(1) xe2x80x94(CH2)nxe2x80x94CH(R13)xe2x80x94, wherein n is an integer from 0 to about 5, and R13 is hydrogen, cycloalkyl having 3-8 carbon atoms, alkyl having 1-6 carbon atoms, or (CH2)mR14; where m is an integer from 0 to about 12 and R14 is a lipophilic substituent of 6 to 20 carbon atoms;
(2) a carbocyclic group having 3-8 ring carbon atoms, wherein the group can be for example, cycloalkyl or aromatic groups, and which can include alkyl having 1-6 carbon atoms, alkoxy having 1-6 carbon atoms, alkylamino having 1-6 carbon atoms, dialkylamino wherein each alkyl independently has 1-6 carbon atoms, amino, sulfonyl, hydroxy, carboxy, fluoro or chloro substituents; or (3) a heterocyclic group, having 3-8 ring atoms, which can include heterocycloalkyl or heteroaromatic groups, which can include from 1 to 4 heteroatoms selected from the group consisting of oxygen, nitrogen, sulfur and mixtures thereto, and which can include alkyl having 1-6 carbon atoms, alkoxy having 1-6 carbon atoms, alkylamino having 1-6 carbon atoms, dialkylamino wherein each alkyl independently has 1-6 carbon atoms, amino, sulfonyl, hydroxy, carboxy, fluoro or chloro substituents.
R9 is a straight chain aliphatic group of 1 to 12 carbon atoms, and R10, R11 and R12 are independently hydrogen, an alkyl group of 1-4 carbon atoms. R9 preferably comprises 2-10 carbon atoms, more preferably, 3-8. R14 preferably includes an intercalating group, which is preferably an acrydine or ethydium bromide group. The number of such repeating units in the polymer is preferably between about 3 and 50, more preferably between about 5 and 20. This, polymer structure can be incorporated into other embodiments of the invention as an R-type segment or polycationic polymer. The ends of this polymer can be modified with a lipid substituent. The monomers that are used to synthesize polymers of this embodiment are suitable for use as the monomers fed to a DNA synthesizer, as described below. Thus, the polymer can be synthesized very specifically. Further, the additional incorporation of polynucleotide sequences, polyether blocks, and lipophilic substituents can be done using the advanced automation developed for polynucleotide syntheses. The fifth embodiment also encompasses this method of synthesizing a polycationic polymer.
In yet another embodiment, the invention relates to a polymer of a plurality of covalently bound polymer segments wherein said segments comprise (a) at least one polycation segment which segment is a cationic homopolymer, copolymer, or block copolymer comprising at least three aminoalkylene monomers, said monomers being selected from the group consisting of:
(i) at least one tertiary amino monomer of the formula: 
and the quaternary salts of said tertiary amino monomer, and (ii) at least one secondary amino monomer of the formula: 
and the acid addition and quaternary salts of said secondary amino monomer, in which:
R1 is hydrogen, alkyl of 2 to 8 carbon atoms, an A monomer, or a B monomer; each of R2 and R3, taken independently of the other, is the same or different straight or branched chain alkanediyl group of the formula:
xe2x80x94(CzH2z)xe2x80x94
in which z has a value of from 2 to 8; R4 is hydrogen satisfying one bond of the depicted geminally bonded carbon atom; and R5 is hydrogen, alkyl of 2 to 8 carbon atoms, an A monomer, or a B monomer; R6 is hydrogen, alkyl of 2 to 8 carbon atoms, an A monomer, or a B monomer; R7 is a straight or branched chain alkanediyl group of the formula:
xe2x80x94(CzH2z)xe2x80x94
in which z has a value of from 2 to 8; and R8 is hydrogen, alkyl of 2 to 8 carbon atoms, an A monomer, or a B monomer; and
(b) at least one straight or branched chained polyether segment having from about 5 to about 400 monomeric units which is:
(i) a homopolymer of a first alkyleneoxy monomer xe2x80x94OCnH2nxe2x80x94 or
(ii) a copolymer or block copolymer of said first alkyleneoxy monomer and a second different alkyleneoxy monomer xe2x80x94OCmH2mxe2x80x94, in which n has a value of 2 or 3 and m has a value of from2to 4.
The preferred polycationic segments include but are not limited to polyamines (e.g., spermine, polyspermine, polyethyleneimine, polypropyleneimine, polybutileneimine, polypentyleneimine, polyhexyleneimine and copolymers thereof), copolymers of tertiary amines and secondary amines, partially or completely quaternized amines, polyvinyl pyridine and the quaternary ammonium salts of these polycation segments. Preferred polycation segments also include aliphatic, heterocyclic or aromatic ionenes (Rembaum et al. Polymer letters, 1968, 6; 159; Tsutsui, T., In Development in ionic polymers -2, Wilson A. D. and Prosser, H. J. (eds.) Applied Science Publishers, London, New York, vol. 2, pp. 167-187, 1986). Particularly preferred polycationic segments include a plurality of cationic repeating units of formula xe2x80x94Nxe2x80x94R0, wherein R0 is a straight chain aliphatic group of 2 to 6 carbon atoms, which may be substituted. Each xe2x80x94Nxe2x80x94R0xe2x80x94 repeating unit in an polycation segment can be the same or different from another xe2x80x94Nxe2x80x94R0xe2x80x94 repeating unit in the segment.
The polycationic segments in the copolymers of the invention can be branched. For example, polyspermine-based copolymers are branched. The cationic segment of these copolymers was synthesized by condensation of 1,4-dibromobutane and N-(3-aminopropyl)-1,3-propanediamine. This reaction yields highly branched polymer products with primary, secondary, and tertiary amines.
An example of branched polycations are products of the condensation reactions between polyamines containing at least 2 nitrogen atoms and alkyl halides containing at least 2 halide atoms (including bromide or chloride). In particular, the branched polycations are produced as a result of polycondensation. An example of this reaction is the reaction between N-(3-aminiopropyl)-1,3-propanediamine and 1,4-dibromobutane, producing polyspermine.
Another example of a branched polycation is polyethyleneimine represented by the formula:
(NHCH2CH2)x[N(CH2CH2)CH2CH2]y
Additionally, cationic dendrimers, for example, polyamidoamines or polypropyleneimines of various generations (i.e., molecular weight), (Tomalia et al., Angew. Chem., Int. Ed. Engl. 1990, 29, 138) can be also used as polycation segments of block copolymers for gene delivery.
In yet another embodiment, the invention relates to a polymer of a plurality of covalently bound polymer segments wherein the segments comprise:
(a) at least one polycation segment which is a cationic homopolymer or copolymer comprising at least three cationic amino acids, or at least three aminoalkylene monomers, the monomers selected from the group consisting of:
(i) at least one tertiary amino monomer of the formula: 
and the quaternary salts of said tertiary amino monomer, and (ii) at least one secondary amino monomer of the formula: 
and the acid addition and quaternary salts of said secondary amino monomer, in which:
R1 is hydrogen, alkyl of 2 to 8 carbon atoms, an A monomer, or a B monomer; each of R2 and R3, taken independently of the other, is the same or different straight or branched chain alkanediyl group of the formula:
xe2x80x94(CzH2z)xe2x80x94
in which z has a value of from 2 to 8; R4 is hydrogen satisfying one bond of the depicted geminally bonded carbon atom; and R5 is hydrogen, alkyl of 2 to 8 carbon atoms, an A monomer, or a B monomer; R6 is hydrogen, alkyl of 2 to 8 carbon atoms, an A monomer, or a B monomer; R7 is a straight or branched chain alkanediyl group of the formula:
xe2x80x94(CzH2z)xe2x80x94
in which z has a value of from 2 to 8; and R8 is hydrogen, alkyl of 2 to 8 carbon atoms, an A monomer, or a B monomer; and
(b) at least one water-soluble nonionic polymer segment. This includes at least one nonionic polymer segment comprising at least three of the same or different repeating units containing at least one atom selected from the group consisting of oxygen and nitrogen.
In this embodiment the polycation serves as the binding segment, while the nonionic polymer serves as a lypohilizing segment.
The polycation segments preferred in this embodiment are the same as polycations preferred in the previous embodiments. These preferred polycation segments include but are not limited to polyamines (e.g., spermine, polyspermine, polyethyleneimine, polypropyleneimine, polybutilene-imine, poolypentyleneimine, polyhexyleneimine and copolymers thereof), copolymers of tertiary amines and secondary amines, partially or completely quaternized amines, polyvinyl pyridine and the quaternary ammonium salts of said polycation segments.
It is preferred that nonionic polymer segments comprise water-soluble polymers, which are nontoxic and nonimunogenic. The preferred nonionic polymer segment is at least one water-soluble nonionic polymer segment is a homopolymer or copolymer of at least one of the monomers selected from the group consisting of acrylamide, gycerol, vinylalcohol, vinylpyrrolidone, vinylpyridine, vinylpyridine N-oxide, oxazoline, or a acrifoge morpholine, and derivatives thereof. This includes for example polyacrylamides, polygycerols, polyvinylalcohols, polyvinylpyrrolidones, polyvinylpyridine N-oxides, copolymers of vinylpyridine N-oxide and vinylpyridine, polyoxazolines, polyacroylmorpholines or derivatives thereof. Nonionic segments comprising products of polymerization of vinyl monomers are also preferred, including but not limiting to the following nonionic polymer segments and derivatives thereof: 
in which m a value of from 3 to about 10,000.
Included within the scope of the invention are compositions comprising these polymers and a suitable targeting molecule. Also included within the scope of the invention are compositions comprising polymer, a polynuclcotide, and a surfactant. The invention also relates to copolymers comprising at least one polynucleotide segment and at least one polyether segment, said polyether segment comprising oxyethylene and oxypropylene.
The present compositions can be used in a variety of treatments. For example, the compositions can be used in Gene therapy including gene replacement or excision therapy, and gene addition therapy, (B. Huber, Gene therapy for neoplastic diseases; B E Huber and J S Lazo Eds., The New York Academy of Sciences, NY, N.Y., 1994, pp. 6-11). Also, antisense therapy targets genes in the nucleus and/or cytoplasm of the cell, resulting in their inhibition (Stein and Cheng, Science 261:1004, 1993; De Mesmaeker et al. Acc. Chem. Res. 28:366, 1995). Aptamer nucleic acid drugs target both intra- and extracellular proteins, peptides and small molecules. See Ellington and Szostak, Nature (London), 346,818, 1990. Antigen nucleic acid compounds can be used to target duplex DNA in the nucleus. See Helene and Tolume, Biochim, Biophys. Acta 1049:99, 1990. Catalytic polynucleotides target mRNA in the nucleus and/or cytoplasm (Cech, Curr. Opp. Struct. Biol. 2:605, 1992).
Examples of genes to be replaced, inhibited and/or added include, but are not limited to, adenosine deaminase, tumor necrosis factor, cell growth factors, Factor IX, interferons (such as xcex1-, xcex2- and xcex3- interferon), interleukins (such interleukin 2,4, 6 and 12), HLA-B7, HSV-TK, CFTR, HIV -1, xcex2-2, microglobulin, retroviral genes (such as gag, pol, env, tax, and rex), cytomegalovirus, herpes viral genes (such as herpes simplex virus type I and II genes ICP27/UL54, ICP22/US1, ICP/IE175, protein kinase and exonuclease/UL13, protein kinase/US3, ribonuclease reductase ICP6/UL39, immediate early (IE) mRNA IE3/IE175/ICP4, 1E4/ICP22/US1, IE5/ICP47, IE110, DNA polymerase/UL30, UL13), human multidrug resistance genes (such as mdrl), oncogenes (such as H-c-ras, c-myb, c-myb, bcl-2, bcr/abl), tumor suppressor gene p53, human MHC genes (such as class 1 MHC), immunoglobulins (such as IgG, IgM, IgE, IgA), hemoglobin xcex1- and xcex2- chains, enzymes (such as carbonic anhydrase, triosephoshate isomerase, GTP-cyclhydrdolase I, phenylalanine hydrolase, sarcosine dehydrogenase, glucocerobrosidase, glucose-6-phosphate dehydrogenase), dysotrophin, fibronectin, apoliprotein E, cystic fibrosis transmembrane conductance protein, c-src protein, V(D)J recombination activating protein, immunogenes, peptide and protein antigens (xe2x80x9cDNA vaccinexe2x80x9d) and the like.
Genetic diseases can also be treated by the instant compositions. Such diseases include, but are not limited to, rheumatoid arthritis, psoriasis, Crohn""s disease, ulcerative colitis, xcex1-thalassemia, xcex2-thalassemia, carbonic anhydrase II deficiency syndrome, triosephosphate isomerase deficiency syndrome, tetrahydrobiopterindeficient hyperphenylalaniemia, classical phenylketonuria, muscular dystrophy such as Duchenne Muscular Dystrophy, hypersarkosinemia, adenomatous intestinal polyposis, adenosine deaminase deficiency, malignant melanoma, glucose-6-phosphste dehydrogenase deficiency syndrome, arteriosclerosis and hypercholesterolemia, Gaucher""s disease, cystic fibrosis, osteopetrosis, increased spontaneous tumors, T and B cell immunodeficiency, high cholesterol, arthritis including chronic rheumatoid arthritis, glaucoma, alcoholism and the like.
The compositions can also be used to treat neoplastic diseases including, but not limited to, breast cancer (e.g., breast, pancreatic, gastric, prostate, colorectal, lung, ovarian), lymphomas (such as Hodgkin and non-Hodgkin lymphoma), melanoma and malignant melanoma, advanced cancer hemophilia B, renal cell carcinoma, gliblastoma, astrocytoma, gliomas, AML and CML and the like.
Additionally, the compositions can be used to treat (i) cardiovascular diseases including but not limited to stroke, cardiomyopathy associated with Duchenne Muscular Dystrophy, myocardial ischemia, restenosis and the like, (ii) infectious diseases such as Hepatitis, HIV infections and AIDS, Herpes, CMV and associated diseases such as CMV renitis, (iii) transplantation related disorders such as renal transplant rejection and the like, and (iv) are useful in vaccine therapies and immunization, including but not limited to melanoma vaccines, HIV vaccines, malaria, tuberculosis, and the like.
Target Cells
Cell targets can be ex vivo and/or in vivo, and include T and B lymphocytes, primary CML, tumor infiltrating lymphocytes, tumor cells, leukemic cells (such as HL-60, ML-3, KG-1 and the like), skin fibroblasts, myoblasts, cells of central nervous system including primary neurons, liver cells, carcinoma (such as Bladder carcinoma T24, human colorectal carcinoma Caco-2), melanoma, CD34+ lymphocytes, NK cells, macrophages, hemotopoetic cells, neuroblastoma (such as LAN-5 and the like), gliomas, lymphomas (such as Burkitt lymphomas ST486), JD38), T-cell hybridomas, muscle cells such as primary smooth muscle, and the like.
Filed concurrently with the parent of this application (Nov. 18, 1994) was Ser. No. 08/342,079 entitled xe2x80x9cPOLYMER LINKED BIOLOGICAL AGENTSxe2x80x9d. The entire disclosure of that application is incorporated herein by reference.
The degree of polymerization of the hydrophilic (A-type) segments or the hydrophobic (B-type) segments of formulas (I)-(XIII) can preferably be between about 5 and about 400. More preferably, the degree of polymerization is between about 5 and about 200, still more preferably, between about 5 and about 80. The degree of polymerization of the R-type polycation segments can preferably be between about 2 and about 300. More preferably, the degree of polymerization is between about 5 and about 180, still more preferably, between about 5 and about 60. The degree of polymerization of the polycationic polymer can preferably be between about 10 and about 10,000. More preferably, the degree of polymerization is between about 10 and about 1,000, still more preferably, between about 10 and about 100.
The repeating units that comprise the segments, for A-type, B-type and R-type segments, will generally have molecular weight between about 30 and about 500, preferably between about 30 and about 100, still more preferably between about 30 and about 60. Generally, in each of the A-type or B-type segments, at least about 80% of the linkages between repeating units are ether linkages, preferably, at least about 90% are ether linkages, more preferably, at least about 95% are ether linkages. Ether linkages, for the purposes of this application, encompass glycosidic linkages (i.e., sugar linkages). However, in one aspect, simple ether linkages are preferred.
The polynucleotide component (pN) of formulas (IX) through (XIII) will preferably comprise from about 5 to about 1,000,000 bases, more preferably about 5 to about 100,000 bases, yet more preferably about 10 to about 10,000 bases.
The polycation segments have several positively ionizable groups and a net positive charge at physiologic pH. The polyether/polycation polymers of formulas (V)-(VIII) can also serve as polycationic polymers. Preferably, the polycation segments have at least about 3 positive charges at physiologic pH, more preferably, at least about 6, still more preferably, at least about 12. Also preferred are polymers or segments that, at physiologic pH, can present positive charges with a distance between the charges of about 2 xc3x85 to about 10 xc3x85. The distances established by ethtyleneimine, aminopropylene, aminobutilene, aminopentylene and aminohehhylene repeating units, or by mixtures of at least two of these groups are most preferred. Preferred are polycationic segments that utilize (NCH2CH2), (NCH2CH2CH2), (NCH2CH2CH2CH2), (NCH2CH2CH2CH2CH2), and (NCH2CH2CH2CH2CH2CH2) repeating units, or a mixture thereof.
Polycation segments having an xe2x80x94Nxe2x80x94R0xe2x80x94 repeating unit are also preferred. R0 is preferably an ethylene, propylene, butylene, pentylene, or hexylene which can be modified. In a preferred embodiment, in at least one of the repeating units R0 includes a DNA intercalating group such as an ethidium bromide group. Such intercalating groups can increase the affinity of the polymer for nucleic acid. Preferred substitutions on R0 include alkyl of 1-6 carbon atoms, hydroxy, hydroxyalkyl, wherein the alkyl has 1-6 carbon atoms, alkoxy having 1-6 carbon atoms, an alkyl carbonyl group having 2-7 carbon atoms, alkoxycarbonyl wherein the alkoxy has 1-6 carbon atoms, alkoxycarbonylalkyl wherein the alkoxy and alkyl each independently has 1-6 carbon atoms, alkylcarboxyalkyl wherein each alkyl group has 1-6 carbon atoms, aminoalkyl wherein the alkyl group has 1-6 carbon atoms, alkylamino or dialkylamino where each alkyl group independently has 1-6 carbon atoms, mono- or di-alkylaminoalkyl wherein each alkyl independently has 1-6 carbon atoms, chloro, chloroalkyl wherein the alkyl has from 1-6 carbon atoms, fluoro, fluoroalkyl wherein the alkyl has from 1-6 carbon atoms, cyano, or cyano alkyl wherein the alkyl has from 1-6 carbon atoms or a carboxyl group. More preferably, R0 is ethylene, propylene or butylene.
Polymers according to the first embodiment of the invention are exemplified by the block copolymers having the formulas: 
in which x, y, z, i and j have values from about 5 to about 400, preferably from about 5 to about 200, more preferably from about 5 to about 80, and wherein for each R1, R2 pair, one is hydrogen and the other is a methyl group.
Formulas (XIV) through (XVI) are oversimplified in that, in practice, the orientation of the isopropylene radicals within the B segment will be random. This random orientation is indicated in formula (XVII), which is more complete. Such poly(oxyethylene)-poly(oxypropylene) compounds have been described by Santon, Am. Perfumer Cosmet., 72(4):54-58 (1958); Schmolka, Loc. cit. 82(7):25 (1967); Schick, Non-ionic Surfactants, pp. 300-371 (Dekker, NY, 1967). A number of such compounds are commercially available under such generic trade names as xe2x80x9cpoloxamersxe2x80x9d, xe2x80x9cpluronicsxe2x80x9d and xe2x80x9csynperonics.xe2x80x9d Pluronic polymers within the B-A-B formula are often referred to as xe2x80x9creversedxe2x80x9d pluronics, xe2x80x9cpluronic Rxe2x80x9d or xe2x80x9cmeroxapolxe2x80x9d. The xe2x80x9cpolyoxaminexe2x80x9d polymer of formula (XVII) is available from BASF (Wyandotte, Mich.) under the tradename Tetronic(trademark). The order of the polyoxyethylene and polyoxypropylene segments represented in formula (XVII) can be reversed, creating Tetronic R(trademark), also available from BASF. See, Schmolka, J. Am. Oil Soc., 59:110 (1979). Polyoxypropylene-polyoxyethylene block copolymers can also be designed with hydrophilic segments comprising a random mix of ethylene oxide and propylene oxide repeating units. To maintain the hydrophilic character of the segment, ethylene oxide will predominate. Similarly, the hydrophobic segment can be a mixture of ethylene oxide and propylene oxide repeating units. Such block copolymers are available from BASF under the tradename Pluradot(trademark).
The diamine-linked pluronic of formula (XVII) can also be a member of the family of diamine-linked polyoxyethylene-polyoxypropylene polymers of formula: 
wherein the dashed lines represent symmetrical copies of the polyether extending off the second nitrogen, R* is an alkylene of 2 to 6 carbons, a cycloalkylene of 5 to 8 carbons or phenylene, for R1 and R2, either,(a) both are hydrogen or (b) one is hydrogen and the other is methyl, for R3 and R4 either (a) both are hydrogen or (b) one is hydrogen and the other is methyl, if both of R3 and R4 are hydrogen, then one R5 and R6 is hydrogen and the other is methyl, and if one of R3 and R4 is methyl, then both of R5 and R6 are hydrogen.
Those of ordinary skill in the art will recognize, in light of the discussion herein, that even when the practice of the invention is confined for example, to poly(oxyethylene)-poly(oxypropylene) compounds, the above exemplary formulas are too confining. Thus, the units making up the first segment need not consist solely of ethylene oxide. Similarly, not all of the B-type segment need not consist solely of propylene oxide units. Instead, the segments can incorporate monomers other than those defined in formulas (XIV)-(XVII), so long as the parameters of the first embodiment are maintained. Thus, in the simplest of examples, at least one of the monomers in segment A might be substituted with a side chain group as previously described.
In another aspect, the invention relates to a polynucleotide complex comprising a block copolymer at least one of formulas (I)-(XIII), wherein the A-type and B-type segments are substantially made up of repeating units of formula xe2x80x94Oxe2x80x94R9, where R9 is:
(1) xe2x80x94(CH2)nxe2x80x94CH(R6), wherein n is an integer from 0 to about 5 and R6 is hydrogen, cycloalkyl having 3-8 carbon atoms, alkyl having 1-6 carbon atoms, phenyl, alkylphenyl wherein the alkyl has 1-6 carbon atoms, hydroxy, hydroxyalkyl, wherein the alkyl has 1-6 carbon atoms, alkoxy having 1-6 carbon atoms, an alkyl carbonyl group having 2-7 carbon atoms, alkoxycarbonyl, wherein the alkloxy has 1-6 carbon atoms, alkoxycarbonylalkyl, wherein the alkoxy and alkyl each independently has 1-6 carbon atoms, alkylcarboxyalkyl, wherein each alkyl group has 1-6 carbon atoms, aminoalkyl wherein the alkyl group has 1-6 carbon atoms, alkylamine or dialkylamino, wherein each alkyl independently has 1-6 carbon atoms, mono- or di-alkylaminoalkyl wherein each alkyl independently has 1-6 carbon atoms, chloro, chloroalkyl wherein the alkyl has from 1-6 carbon atoms, fluoro, fluoroalkyl wherein the alkyl has from 1-6 carbon atoms, cyano or cyano alkyl wherein the alkyl has from 1-6 carbon atoms or carboxyl; (2) a carbocyclic group having 3-8: ring carbon atoms, wherein the group can be for example, cycloalkyl or aromatic groups, and which can include alkyl having 1-6 carbon atoms, alkoxy. having 1-6 carbon atoms, alkylamino having 1-6 carbon atoms, dialkylamino wherein each alkyl independently has 1-6 carbon atoms, amino, sulfonyl, hydroxy, carboxy, fluoro or chloro substitutions, or (3) a heterocyclic group, having 3-8 ring atoms, which can include heterocycloalkyl or heteroaromatic groups, which can include from 1-4 heteroatoms selected from the group consisting of oxygen, nitrogen, sulfur and mixtures thereto, and which can include alkyl having 1-6 carbon atoms, alkoxy having 1-6 carbon atoms, alkylamino having 1-6 carbon atoms, dialkylamino wherein each alkyl independently has 1-6 carbon atoms, amino, sulfonyl, hydroxy, carboxy, fluoro or chloro substitutions.
Preferably, n is an integer from 1 to 3. The carbocyclic or heterocyclic groups comprising R5 preferably have from 4-7 ring atoms, more preferably 5-6. Heterocycles preferably include from 1-2 heteroatoms, more preferably, the heterocycles have one heteroatom. Preferably, the heterocycle is a carbohydrate or carbohydrate analog. Those of ordinary skill will recognize that the monomers required to make these polymers are synthetically available. In some cases, polymerization of the monomers will require the use of suitable protective groups, as will be recognized by those of ordinary skill in the art. Generally, the A- and B-type segments are at least about 80% comprised of xe2x80x94OR5xe2x80x94 repeating units, more preferably at least about 90%, yet more preferably at least about 95%.
In another aspect, the invention relates to a polynucleotide complex comprising a block copolymer of one of formulas (I)-(XIII) wherein the A-type and B-type segments consist essentially of repeating units of formula xe2x80x94Oxe2x80x94R5 wherein R7 is a C to C alkyl group.
A wide variety of nucleic acid molecules can be the nucleic acid component of the composition. These include natural and synthetic DNA or RNA molecules and nucleic acid molecules that have been covaleritly modified (to incorporate groups including lipophilic groups, photo-induced crosslinking groups, alkylating groups, organometallic groups, intercalating groups, lipophilic groups, biotin, fluorescent and radioactive groups, and groups that modify the phosphate backbone). Such nucleic acid molecules can be, among other things, antisense nucleic acid molecules, gene-encoding DNA (usually including an appropriate promoter sequence), ribozymes, aptamers, antigen nucleic acids, oligonucleotide xcex1-anomers, ethylphosphotriester analogs, alkylphosphomates, phosphorothionate and phosphorodithionate oligonucleotides, and the like. In fact, the nucleic acid component can be any nucleic acid that can beneficially be transported into a cell with greater efficiency, or stabilized from degradative processes, or improved in its biodistribution after administration to an animal.
Examples of useful polymers pursuant to formulas (V)-(VIII) include the poly(oxyethylene)-poly-L-lysine) diblock copolymer of the following formula: 
wherein i is an integer of from about 5 to about 100, and j is an integer from about 4 to about 100. A second example is the poly(oxyethylene)-poly-(L-alanine-L-lysine) diblock copolymer of formula: 
wherein i is an integer of from about 5 to about 100, and j is an integer from about 4 about 100. A third example is the poly(oxyethylene)-poly(propyleneimine/butyleneimine) diblock copolymer of the following formula: 
wherein i is an integer from about 5 about 200 and j is an integer from 1 to about 10. A fourth example is the poly(oxyethylene)-poly(N-ethyl-4-vinylpyridinium bromide) (xe2x80x9cpOE-pEVP-Brxe2x80x9d) of formula: 
wherein i is an integer of from about 5 to about 100 and j is an integer of from about 10 to about 500. Still another example is the polymer of formula:
CH3Oxe2x80x94(CH2CH2O)iCO[(NH(CH2)3)2NH(CH2)4]jxe2x80x94(NH(CH2)3)2xe2x80x94NCHOxe2x80x94Oxe2x80x94(CH2CH2O)kxe2x80x94CH3xe2x80x83xe2x80x83(XXII)
wherein i is an integer from about 10 to about 200, j is an integer from about 1 to about 8, and k is an integer from about 10 to about 200. Still another example is the polymer of formula:
Hxe2x80x94Gjxe2x80x94(NH(CH2)3)2xe2x80x94Nxe2x80x94NHxe2x80x94COxe2x80x94Oxe2x80x94(CH2CH2O)iCOxe2x80x94Gmxe2x80x94(NH(CH2)3)2xe2x80x94NH2xe2x80x83xe2x80x83(XXIII)
wherein xe2x80x9cGxe2x80x9d comprises xe2x80x94(NH(CH2)3)3xe2x80x94CH2NH2xe2x80x94, i and j are as defined for formula (XVIII), and m is an integer from about 1 to about 8.
The block copolymers utilized in the invention will typically, under certain circumstances, form micelles or micelle-like aggregates of from about 10 nm to about 100 nm in diameter. Micelles are supramolecular complexes of certain amphiphilic molecules that form in aqueous solutions due to microphase separation of the nonpolar portions of the amphiphiles. Micelles form when the concentration of the amphiphile reaches, for a given temperature, a critical micellar concentration (xe2x80x9cCMCxe2x80x9d) that is characteristic of the amphiphile. Such micelles will generally include from about 10 to about 300 block copolymers. By varying the sizes of the hydrophilic and hydrophobic portions of the block copolymers, the tendency of the copolymers to form micelles at physiological conditions can be varied. The micelles have a dense core formed by the water insoluble repeating units of the B blocks and charge-neutralized nucleic acids, and a hydrophilic shell formed by the A segments. The micelles have translational and rotational freedom in solution, and solutions containing the micelles have low viscosity similar to water. Micelle formation typically occurs at copolymer concentrations from about 0.001 to 5% (w/v). Generally, the concentration of polycationic polymers and polynucleic acid will be less than the concentration of copolymers in the polynucleotide compositions, preferably at least about 10-fold less, more preferably at least about 50-fold.
At high concentrations, some of the block copolymers utilized in the invention will form gels. These gels are viscous systems in which the translational and rotational freedom of the copolymer molecules is significantly constrained by a continuous network of interactions among copolymer molecules. In gels, microsegregation of the B segment repeating units may or may not occur. To avoid the formation of gels, polymer concentrations (for both block copolymers and polyether/polycation polymers) will preferably be below about 15% (w/v), more preferably below about 10%, still more preferably below about 5%. In the first embodiment of the invention, it is more preferred that gels be avoided.
When the polynucleotide composition includes cationic components, the cations will associate with the phosphate groups of the polynucleotide, neutralizing the charge on the phosphate groups and rendering the polynucleotide component more hydrophobic. The neutralization is preferably supplied by cations on R-type polymeric segments or on polycationic polymers. However, the phosphate charge can also be neutralized by chemical modification or by association with a hydrophobic cations such as N-[1-(2,3-dioleyloxy)-N,Nxe2x80x2-3-methylammoniurn chloride]. In aqueous solution, the charge neutralized polynucleotides are believed to participate in the formation of supramolecular, micelle-like particles, termed xe2x80x9cpolynucleotide complexes.xe2x80x9d The hydrophobic core or the complex comprises the charge neutralized polynucleotides and the B-type segments. The hydrophilic shell comprises the A-type segments. The size of the complex will generally vary from about 10 nm to about 100 nm in diameter. In some contexts it is practical to isolate the complex from unincorporated components. This can be done for instance, by gel filtration chromatography.
The ratio of the components of the polynucleotide composition is an important factor in optimizing the effective transmembrane permeability of the polynucleotides in the composition. This ratio can be identified as ratio Ø, which is the ratio of positively charged groups to negatively charged groups in the composition at physiological pH. If Ø less than 1, the complex contains non-neutralized phosphate from the polynucleotide. The portions of the polynucleotides adjacent to the non-neutralized charges are believed to be a part of the shell of a polynucleotide complex. Correspondingly, if Ø greater than 1, the polycationic polymer or R-type segment will have non-neutralized charges, and the un-neutralized portions will fold so that they form a part of the shell of the complex. Generally, Ø will vary from about 0 (where there are no cationic groups) to about 100, preferably Ø will range between about 0.01 and about 50, more preferably, between about 0.1 and about 20. Ø can be varied to increase the efficiency of transmembrane transport and, when the composition comprises polynucleotide complexes, to increase the stability of the complex. Variations in Ø can also affect the biodistribution of the complex after administration to an animal. The optimal Ø will depend on, among other things, (1) the context in which the polynucleotide composition is being used, (2) the specific polymers and oligonucleotides being used, (3) the cells or tissues targeted, and (4) the mode of administration.
It will in some circumstances be desirable to incorporate in the polynucleotide compositions of the current invention, by noncovalent association or covalent conjugation, targeting molecules. See for example, Kabanov et al, J. Controlled Release, 22:141 (1992), the contents of which are hereby incorporated by reference. The term xe2x80x9ctargeting moleculexe2x80x9d means any molecule, atom, or ion that enhances binding, transport, accumulation, residence time, bioavailability or modifies biological activity of the polynucleotides or the polynucleotide compositions of the current invention in the body or cell. The targeting molecule will frequently comprise an antibody, fragment of antibody or chimeric antibody molecule typically with specificity for a certain cell surface antigen. The targeting molecule can also be, for instance, a hormone having a specific interaction with a cell surface receptor, or a drug having a cell surface receptor. For example, glycolipids can serve to targetia polysaccharide receptor. The targeting molecules can also be, for instance, enzymes, lectins, and polysaccharides low molecular mass ligands, such as folic acid and derivatives thereof are also useful in the context of the current invention. The targeting molecules can also be polynucleotide, polypeptide, peptidomimetic, carbohydrates including polysaccharides, derivatives thereof or other chemical entities obtained by means of combinatorial chemistry and biology. The targeting molecules can be used to facilitate intracellular transport of the polynucleotide compositions of the invention, for instance transport to the nucleus, by using, for example, fusogenic peptides as targeting molecules described by Soukchareun et al., Bioconjugate Chem., 6, 43 (1995), or Arar et al., Bioconjugate Chem., 6, 43 (1995), caryotypic peptides, or other biospecific groups providing site-directed transport into a cell (in particular, exit from endosomic compartments into cytoplasm, or delivery to the nucleus).
Included within the scope of the invention are compositions comprising the polynucleotide, block copolymer of the current invention and a suitable targeting molecule. The targeting molecule can be covalently linked to any of the polymer segments of the block copolymers identified herein (or polynucleotide complexes thereof), including cationic and nonionic polymer segments. For instance, the targeting molecule can be linked to the free-terminal or pendant groups of the nonionic segments. Such targeting molecules can be linked to the terminal or pendant xe2x80x94OH end group of the polymer segments, and the terminal or pendant xe2x80x94NH2 group of the polymer segments, or the terminal or pendant xe2x80x94COOH end group of the polymer segments, or the like.
It will in some circumstances be desirable to incorporate targeting molecules through ligand-receptor constructs, in which:
(i) the ligand molecule is a chemical entity (e.g., a molecule, atom, or ion) capable of specific binding with the receptor molecule; (ii) the receptor molecule is a chemical entity capable of specific binding to the ligand molecule; or (iii) the ligand molecules, receptor molecules (or both) are incorporated into the block copolymers (or polynucleotide complexes thereof), targeting molecules, or both. This is done by noncovalent association or covalent conjugation so that after (i) mixing targeting molecules and block copolymers (or polynucleotide complexes thereof) with the ligand and receptor molecules attached to them, or (ii) by adding either free ligand or receptor (or both) to the mixture of targeting molecules and block copolymers (or polynucleotide complexes thereof), the targeting molecule becomes attached to the block copolymers (or to the polynucleotide complexes thereof) through ligand-receptor binding. Examples of such constructs include constructs using biotin as the ligand and avidin or streptavidin as the receptor. For example, biotin or a derivative thereof can be covalently linked to the block copolymers (or polynucleotide complexes thereof) of the current invention and avidin (or streptavidin) can be covalently linked to the targeting molecule. Alternatively, biotin can be linked to both the block copolymers (or polynucleotide complexes thereof) and targeting molecule, and the latter can be linked through avidin, which has four biotin-binding centers. Further, additional complex constructs comprising biotin and avidin can be used for incorporating targeting molecules in polynucleotide compositions of the current invention. In one particular embodiment, the invention provides for the block copolymers (or polynucleotide complexes thereof) with biotin molecules or derivatives thereof linked to at least one polycation or nonionic polymer segments or both polycation and nonionic polymer segments. Those of ordinary skill in the art will ecognize, in light of the discussion herein, that even when the practice of the invention is confined for example, to biotin-avidin or biotin-streptavidin constructs or the similar constructs, there are numerous ways available providing for the design of the ligand-receptor constructs with the desired characteristics pursuant to this invention. Such constructs, for example, can comprise ligands and/or receptors that are polynucleotide, polypeptide, peptidomimetic, carbohydrates including polysaccharides, derivatives thereof or other chemical entities obtained by means of combinatorial chemistry and biology.
The targeting molecules which can be associated with the polynucleotide compositions of the invention can also have a targeting group having affinity for a cellular site and a hydrophobic group. Such targeting molecules can provide for the site specific delivery and recognition in the body. The targeting molecule spontaneously associates with the polynucleotide complex and be xe2x80x9canchoredxe2x80x9d thereto through the hydrophobic group. These targeting adducts will typically comprise about 1% or less of the polymers in a final composition. In the targeting molecule, the hydrophobic group can be, among other things, a lipid group such as a fatty acyl group. Alternatively, it can be an ionic or nonionic homopolymer, copolymer, block copolymer, graft copolymer, dendrimer or another natural or synthetic polymer.
In the targeting molecule, the hydrophobic group can be, among other things, a lipid group such as a fatty acyl group. Alternately, it can be a block copolymer or another natural synthetic polymer. The targeting group of the targeting molecule will frequently comprise an antibody, typically with specificity for a certain cell surface antigen. It could also be, for instance, a hormone having a specific interaction with a cell surface receptor, or a drug having a cell surface receptor. For example, glycolipids could serve to target a polysaccharide receptor. It should be noted that the targeting molecule can be attached to any of the polymer segments identified herein, including R-type polymeric segments and to the polycationic polymers. For instance, the targeting molecule can be covalently attached to the free-terminal groups of the polyether segment of the block copolymer of the invention. Such targeting molecules can be covalently attached to the xe2x80x94OH end group of the polymers of the formulas XVIII, XIX, XX, and XXI, and the xe2x80x94NH2 end group of the polymers of formulas XVIII (preferably the xcex5-amino group of the terminal lysyl residue), XX or XXIII, or the xe2x80x94COOH end group of the polymers of formulas XVIII and XIX. Targeting molecules can be used to facilitate intracellular transport of the polynucleotide composition, for instance transport to the nucleus, by using, for example, fusogenic peptides as targeting molecules described by Soukchareun et al., Bioconjugate Chem., 6, 43, 1995 or Arar et al., Bioconjugate Chem., 6, 43, 1995, caryotypic peptides, or other biospecific groups providing site-directed transport into a cell (in particular, exit from endosomic compartments into cytoplasm, or delivery to the nucleus).
The polynucleotide component of the compositions of the invention can be any polynucleotide, but preferably a polynucleotide with at least about 3 bases, more preferably at least about 5 bases. Still more preferred are at least 10 bases. Included among the suitable polynucleotides are viral genoimes and viruses (including the lipid or protein viral coat). This includes viral vectors including, but not limited to, retroviruses, adenoviruses, herpes-virus, and Pox-viruses. Other suitable viral vectors for use with the present invention will be obvious to those skilled in the art. The terms xe2x80x9cpoly(nucleic acid)xe2x80x9d and xe2x80x9cpolynucleotidexe2x80x9d are used interchangeably herein. An oligonucleotide is a polynucleotide, as are DNA and RNA.
A polynucleotide derivative is a polynucleotide having one or more moieties (i) wherein the moieties are cleaved, inactivated or otherwise transformed so that the resulting material can function as a polynucleotide, or (ii) wherein the moiety does not prevent the derivative from functioning as a polynucleotide.
For polyethylene oxide-polypropylene oxide copolymers, the hydrophilic/hydrophobic properties, and micelle forming properties of a block copolymer are, to a certain degree, related to the value of the ratio, n. The ratio, n, is defined as:
xe2x80x83n=(|B|/|A|)x(b/a)=(|B|/|A|)x1.32
where |B| and |A| are the number of repeating units, in the hydrophobic and hydrophilic segments of the copolymer, respectively, and b and a are the molecular weights for the respective repeating units. The value of n will typically be between about 0.2 and about 9.0, more preferably, between about 0.2 and about 1.5. Where mixtures of block copolymers are used, n will be the weighted average of n for each contributing copolymers, with the averaging based on the weight portions of the comlponent copolymers. When copolymers other than polyethylene oxide-polypropylene oxide copolymers are used, similar approaches can be developed to relate the hydrophobic/hydrophilic properties of one member of the class of polymers to the properties of another member of the class.
Surfactant-Containing Polynucleotide Compositions
The invention also includes compositions of polynucleotide, cationic copolymer, and a suitable surfactant. The surfactant, should be (i) cationic (including those used in various transfection cocktails), (ii) non ionic (e.g., Pluronic or Tetronic), or (iii) zwitterionic (including betains and phospholipids). These surfactants increase solubility of the complex and increase biological activity of the compositions.
Cationic surfactants include but are not limited to primary amines, secondary amines, tertiary amines (e.g., N,Nxe2x80x2,Nxe2x80x2-polyoxyethylene(10)-N-tallow-1,3-diaminopropane), quaternary amine salts (e.g., dodecyltrimethylammonium bromide, hexadecyltrimethylammonium bromide, mixed alkyl-trimethylammonium bromide, tetradecyltrimethylammonium bromide, benzalkonium chloride, benzethonium chloride, benzyldimethyldodecylammonium chloride, benzyl-dimethylhexadecylammonium chloride, benzyltrimethylammonium methoxide, cetyldimethylethylammonium bromide, dimethyldioctadecyl ammonium bromide, methylbenzethonium chloride, decamethonium chloride, methyl mixed trialkyl ammonium chloride, methyl trioctylamimonium chloride), N,N-dimethyl-N-[2-(2-methyl-4-(1,1,3,3-tetramethylbutyl)-phenoxy]ethoxy)ethyl]-benzenemethanaminium chloride (DEBDA), dialkyldimetylammonium salts, N-[1-(2,3-dioleyloxy)-propyl]-N,N,N,-trimethylammonium chloride, 1,2-diacyl-3-(trimethylammonio)propane (acyl group=dimyristoyl, dipalmitoyl, distearoyl, dioleoyl), 1,2-diacyl-3-(dimethylammonio)propane (acyl group=dimyristoyl, dipalmitoyl, distearoyl, dioleoyl), 1,2-dioleoyl-3-(4xe2x80x2-trimethylammonio) butanoyl-sn-glycerol, 1,2-dioleoyl-3-succinyl-sn-glycerol choline ester, cholesteryl (4xe2x80x2-trimethylammonio) butanoate), N-alkyl pyridinium salts (e.g. cetylpyridinium bromide and cetylpyridinium chloride), N-alkylpiperidinium salts, dicationic bolaform electrolytes (C12Me6; C12Bu6), dialkylglycetyl-phosphorylcholine, lysolecithin, L-xcex1 dioleoyl phosphatidylethanolamine), cholesterol hemisuccinate choline ester, lipopolyamines (e.g., dioctadecylamidoglycylspermine (DOGS), dipalmitoyl phosphatidylethanolamidospermine (DPPES), lipopoly-L(or D)-lysine (LPLL, LPDL), poly(L (or D)-lysine conjugated to N-glutarylphosphatidylethanolamine, didodecyl glutamate ester with pendant amino group (C12GluPhCnN+), ditetradecyl glutamate ester with pendant amino group (C14GluCnN+), cationic derivatives of cholesterol (e.g., cholesteryl-3xcex2-oxy-succinamidoethylenetrimethylammonium salt, cholesteryl-3xcex2-oxysuccinamidoethylenedimethyl-amine, cholesteryl-3xcex2-carboxyamidoethylenetrimethylammonium salt, cholesteryl-3xcex2-carboxy-amidoethylenedimethylamine, 3xcex2[N-(Nxe2x80x2,Nxe2x80x2-dimethylaminoetane-carbomoil]cholesterol).
Non-ionic surfactants include but are not limited to n-Alkylphenyl polyoxyethylene ether, n-alkyl polyoxyethylene ethers (e.g., Tritons(trademark)), sorbitan esters (e.g., Spans(trademark)), polyglycol ether surfactants (Tergitol(trademark)), polyoxyethylenesorbitan (e.g., Tweens(trademark)), polysorbates, poly-oxyethylated glycol monoethers (e.g., Brij(trademark), polyoxylethylene 9 lauryl ether, polyoxylethylene 10 ether, polyoxylethylene 10 tridecyl ether), lubrol, copolymers of ethylene oxide and propylene oxide (e.g., Pluronic(trademark), Pluronic R(trademark), Tetronic(trademark), Pluradot(trademark)), alkyl, aryl polyether alcohol (Tyloxapol(trademark)), perfluoroalkyl polyoxylated amides, N,N-bis[3-D-gluconamidopropyl]cholamide, decanoyl-N-methylglucamide, n-decyl xcex1-D-glucopyranozide, n-decyl xcex2-D-glucopyranozide, n-decyl xcex2-D-maltopyranozide, n-dodecyl xcex2-D-glucopyranozide, n-undecyl xcex2-D-glucopyranozide, n-heptyl xcex2-D-glucopyranozide, n-heptyl xcex2-D-thioglucopyranozide, n-hexyl xcex2-D-glucopyranozide, n-nonanoyl xcex2-D-glucopyranozide 1-monooleyl-rac-glycerol, nonanoyl-N-methylglucarnide, n-dodecyl xcex1-D-maltoside, n-dodecyl xcex2-D-maltoside, N,N-bis[3-gluconamidepropyl]-deoxycholamide, diethylene glycol monopentyl ether, digitonin, heptanoyl-N-methylglucamide, heptanoyl-N-methylglucamide, octanoyl-N-methylglucamide, n-octyl xcex2-D-glucopyranozide, n-octyl xcex1-D-glucopyranozide, n-octyl xcex2-D-thiogalactopyranozide, n-octyl xcex2-D-thioglucopyranozide.
Zwitterionic surfactants include but are not limited to betaine (R1R2R3N+Rxe2x80x2CO2xe2x88x92, where R1R2R3Rxe2x80x2 are hydrocarbon chains and R1 is the longest one), sulfobetaine (R1R2R3N+Rxe2x80x2SO3xe2x88x92), phospholipids (e.g., dialkyl phosphatidylcholine), 3-[(3-cholamidopropyl)-dimethylammonio]-2-hydroxy-1-propanesulfonate, 3 -[(3-cholamidopropyl)-dimethylammonio]-1-propanesulfonate, N-decyl-N,N-dimethyl-3-ammonio-1-propanesulfonate, N-dodecyl-N,N-dimethyl-3-ammonio-1-propane-sulfonate, N-hexadecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate, N-octadecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate, N-octyl-N,N-dimethyl-3-ammonio-1-propane-sulfonate, N-tetradecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate, and dialkyl phosphatidyl-ethanolamine.
The polynucleotide compositions of the invention can be administered orally, topically, rectally, vaginally, by pulmonary route by use of an aerosol, or parenterally, i.e. intramuscularly, subcutaneously, intraperitonealily or intravenously. The polynucleotide compositions can be administered alone, or it can be combined with a pharmaceutically-acceptable carrier or excipient according to standard pharmaceutical practice. For the oral mode of administration, the polynucleotide compositions can be used in the form of tablets, capsules, lozenges, troches, powders, syrups, elixirs, aqueous solutions and suspensions, and the like. In the case of tablets, carriers that can be used include lactose, sodium citrate and salts of phosphoric acid. Various disintegrants such as starch, and lubricating agents such as magnesium stearate, sodium lauryl sulfate and talc, are commonly used in tablets. For oral administration in capsule form, useful diluents are lactose and high molecular weight polyethylene glycols. When aqueous suspensions are required for oral use, the polynucleotide compositions can be combined with emulsifying and suspending agents. If desired, certain sweetening and/or flavoring agents can be added. For parenteral administration, sterile solutions of the conjugate are usually prepared, and the pH of the solutions are suitably adjusted and buffered. For intravenous use, the total concentration of solutes should be controlled to render the preparation isotonic. For ocular administration, ointments or droppable liquids may be delivered by ocular delivery systems known to the art such as applicators or eye droppers. Such compositions can include mucomimetics such as hyaluronic acid, chondroitin sulfate, hydroxypropyl methylcellulose or poly(vinyl alcohol), preservatives such as sorbic acid, EDTA or benzylchronium chloride, and the usual quantities of diluents and/or carriers. For pulmonary administration, diluents and/or carriers are selected to be appropriate to allow the formation of an aerosol.
The following examples will serve to further typify the nature of the invention but should not be construed as a limitation on the scope thereof, which is defined solely by the appended claims.